Prior buckles can be largely classified into two major categories. The first is typified by the invention of U.S. Pat. No. 4,991,272 to Bianchi, which discloses a buckle comprising male and female members. The female member forms a receptacle into which the male member is inserted. The male member has a pair of locking lugs at the end of flexible arms which protrude through openings in the female member. Engagement usually requires the use of both hands of the operator; and, release requires the use of at least two fingers to simultaneously depress the locking lugs. U.S. Pat. No. 5,438,737 to Ansher, which discloses a snap closure with quick release, represents an improvement over this type of buckle through its adaptation for release by pressure from a single finger of the operator. To facilitate ease of use a thinner and thus more flexible male member can be used, however, this introduces weakness into the buckle and reduces the security of the engagement of the buckle components.
The second major category is exemplified by buckles of the type shown in U.S. Pat. No. 5,860,199 to Liu, which discloses a, quick release belt buckle. Engagement involves the insertion of a plug member into a body member, which generally requires the use of both hands of the operator. Release is achieved by pressing a spring loaded button that extends through the top cover plate of the body. This buckle can be made of metal for added strength and durability, however it requires dexterity to operate.
A need remains for a fastener readily usable by persons with limited dexterity due to disability, disease, injury, youth, or advanced age. Such persons often find it difficult or painful to manipulate a buckle requiring the use of both hands to align and insert one component into another to achieve engagement without the assistance of another person. The simultaneous compression of locking lugs to release a buckle can be equally cumbersome and/or painful for persons having these conditions. Accordingly, a primary object of the present invention is to provide an improved clasp or buckle that can be easily operated by persons with impaired manual dexterity yet provides a secure engagement. The present invention thus provides a greater level of independence for people who might otherwise require assistance to perform basic, day-to-day activities, such as dressing themselves.